Ignition or firing mechanism



March 5, 1946- J. w. VAN KARNER 2,395,064

IGNITION OR FIRING MECHANISM FiledDec. 10, 1943 2 Sheets-Sheet 1 Try 7.P

0000 GOGOOOOOOOOO OQ- J JOSEPH w VAN KARNER March 1946- J. w. VAN KARNERIGNITION 0R FIRING MECHANISM Filed Dec. 10, 1943 2 Sheets-Sheet 2 w n 1%2. 5 4 Wm 3 2 3 N N w I: H A M WM mnl Patented Mar. 5, 1946 UNITEDSTATES PATENT OFFICE 2,39 ,064 IGNITION on name MECHANISM Joseph W. VanKhmer, New York, N. Y. ADDlicationDecember 10, 1943, Serial No. 513,7977 (Cl. 102-65) This invention relates to ignition or firing I mechanismsfor smoke signals, gas bombs, hand grenades, sea. or snow markers, andsimilar devices where quick ignition and safety are prime factors.

More specifically, the present invention comprises a support for theignition or firing mechanism which is secured to a wall of a smoke bomb,or other device, and which carries cooperating portions of the firingmechanism, one of the cooperating portions being secured to thesupporting mechanism within the bomb or the like, and the othercooperating part being secured into the outer portion of the support andaccessible from the exterior of the bomb. The respective portions of thefiring mechanism carry cooperating friction igniting means, which may beset into operation by a quick relative movement of the two parts. A fusepreferably is secured to the inner member to be ignited by the frictionignition means and to transmit the fire, after a suitable delay, to thecharge of the bomb or other device to which the ignition means isapplied. Care is taken to ensure a watertight connection between thesupport for the firing mechanism and the wall of the device to which itis secured, and also between the support and the cooperating firingmembers, so that water or moisture from the outside cannot enter anddamage the device, even if it should be dropped into water. To furtherensure that water will not enter the device, a water-tight cap or thelike may be screwed onto it about the ignition or firing mechanism.

The invention will be further described in connection with theaccompanying drawings, in which the ignition means is applied to a smokebomb intended to function as a distress signal. However, it is to beunderstood that such further description is by way of exemplification,and the invention is not limited thereby.

In the drawings: I

Fig. 1 is a vertical sectional view of a distress signal or smoke bombembodying an ignition or firing mechanism constructed in accordance withthe present invention;

Fig. 2 is a plan view;

Fig. 3 is an enlarged view of that portion oi Fig. 1 including theignition or firing mechanism, and

Fig. 4 is an enlarged sectional view of the ignition or firingmechanism, showing the cooperating parts being separated. as during theact of setting the device into operation.

Referring to the drawings, 1 designates the container of a smokedistress signal having a charge of suitable smoke-producing material 1in the bottom thereof. A continuous layer 3 of kraftboard, chip-board orother relatively non-inflammable, heat-insulating, moisture-absorbentmaterial may be placed between the side walls and the bottom of thecontainer and the smoke-producing charge 2 to maintain the latter dryunder all atmospheric conditions.

. The charge of smoke-producing material may have a tube 4 of perforatedmetal or the like inserted in the center thereof to facilitate thecirculation of air within and the better burning of the smoke-producingmaterial.

The charge of smoke-producing material may be maintained in place in thebottom of the container in any desired manner, and to that end a cover 5of nitrocellulose or other readily in flammable material and aperforated supporting plate 6 of metal or the like extend entirelyacross the top of the smoke-producing charge and the upper edge of thelayer of insulating and absorbent material 3. A ferrule or tube 1 ofmaterial similar to the material of the layer 3 extends between theouter edge of the partition plate 6 and the top of the container, andfirmly maintains the charge of smoke-producing material in proper placewithin the container, regardless of the angular position which thec0ntainer may assume.

The top of the container shown in the drawings has an upward extension8, the top of which is depressed and supports at one side thereofignition means which form the subject matter of this application. At theother side the top ,of the extension is provided with an opening 9through which smoke may be discharged after the signal has been set intooperation. A paster l0 normally closes the opening 9 and is removed byrupturing under internal gas pressure, or by being ignited by aquick-flash fuse ll after the charge 2 has been ignited by the ignitionmeans presently to be described.

The ignition means for the charge of smokeproducing material, comprisesa support l2 positioned in a well [3 at one side of the depressedportion of the top of the extension 8. The support comprises an annularportion 14, which extends through the bottom of the Well i3, and anoutwardly extending flange i5 which overlies and rests upon the bottomof the well on the outside. A nut l6 threaded onto the annular portion Il and against the bottom of the'well i3, firmly clamps the support inplace and forms a water-tight connection between the bottom of the welll3 and the support l2. The interior of ing member is tightly screwed inplace, water cannot enter the container through the support l2.

A friction primer 23 in the form of a coil of brass wire, has its upperend extending through a small opening 24 in the closure bushing l3 andattached to the lower end of a short length of flexible cord 25, whichhas its other end extending through a small opening 26 in a brassbushing 21 threaded into a recess in the center of the primer-carryingmember IS. The cord is retained in the bushing 21 by knotting it, theknot being too large to pass through the opening 26 through which thecord extends.

The outer periphery of the annular portion ll of the support I2 isprovided with a groove 28 ad- ,iacent its'lower edge. Afuse-holder-supporting member 29 of relatively rigid wire has an upperring 30 thereof positioned in the groove 28. A lower ring portion 3| ofthe fuse-holder-supporting member 29 embraces a tubular fuse-holder 32into the lower end of which a delayed-action fuse 33 is secured. Thus,the fuse-holder-supporting member 29 supports the fuse 33 from thesupport and maintains it in a proper position with respect to thefriction primer coil 23 and support I2.

The friction primer coil 23 is of such diameter as to bear frictionallyagainst the inside of the fuse-holder 32, the upper portion of which iscoated with a suitable ignitable phosphorus composition 34, so that whenthe primer coil 23 is withdrawn, the friction thereof against thephosphorus coating on the inside of the fuse-holder will ignite thephosphorus coating which, in turn, will ignite the upper end of thedelayed-action fuse 33. To ensure continuous contact of the frictionprimer coil with the phosphorus-coated, inner portion of the fuse holder32 the upper end of the latter is pinched together.

The delayed-action fuse 33 protrudes from the lower end of thefuse-holder a suitable distance, and is connected by a fuse-junctioncover 35 to a safety fuse 36, the lower end of the safety fuse 36extends through the perforated partition plate 6 and the inflammablecover 5, and is embedded in or lapped upon the charge of thesmoke-producing material 2.

' The upper end of the delayed-action fuse 33 is enclosed by a ferrule3| which has prongs 3| struck from the side thereof which bite into theinner side wall of the fuse-holder 32, and prevent withdrawal of thefuse from the fuse-holder 32. The upper end of the ferrule is bent overthe end of the fuse, as shown in Fig. 3, to facilitate its insertioninto the fuse-holder.

The delayed-action fuse 33 and the fuses II and 35 preferably arestandard types of fuses which have been approved by the United StatesArmy or Navy, or other suitable Government 1 agency.

flange 22. The ring 31 normally lies in the depression in the top of theextension 8, as shown in Fig. 1, and is covered by a closure cap 33threaded onto the extension. Suitable gaskets 38 and 40, of corkormaterial similar to the material of gasket 2|, are interposed betweenthe top of the extension 8 and the closure cap 38, and between thebottom of a flange ll of the closure cap and the top of the containertoform water-tight seal.

When it is desired to use the smoke signal or other device embodying theignition means, the closure cap 38 is unscrewed to give access to thepull-ring 31 of the primer-carrying member I3. The primer-carryingmember is then unscrewed from the support l2, after which the ring 38 isgiven a quick pull which causes the primer coil 23 to move frictionallyin contact with the coated or ignitable phosphorus composition 34 on theinside of the fuse-holder 32, with the result that the phosphoruscomposition is ignited and, in turn, ignites the delayed-action fuse 33.The delayed action fuse, after a predetermined period, depending uponthe length and nature thereof, sets the device into operation, either byigniting a smoke-producing charge or the like, or by the setting off ofan explosive charge, if the device is a grenade, explosive bomb, or thelike.

From the foregoing description it will be understood that the presentinvention provides ignition or firing means for a signal, bomb, or thelike,

which embodies allof the desired characteristics of quick ignition,after a predetermined period, safety and maintenance of the device towhich it is applied in operable condition regardless of climaticconditions, and even if the device should be dropped into water. Also,the ignition means is one which readily may be set into operationwithout any special tools or equipment, and by persons who previouslyhave had no experience with such devices.

What I claim is:

1. An ignition or firing mechanism comprising a support, afuse-holder-supporting member secured to said support, a tubularfuse-holder carried' by said fuse-holder-supporting member in fixedrelation to said support, a delayed-action fuse secured within one endof said fuse-holder. the other end of said fuse-holder having a coatingof frictioii-ignitable material on the inside thereof, aprimer-coil-carrying member threaded into the support, means between theprimercoil-carrying member and the support for making a water-tight sealbetween the two, a friction primer coil carried by theprimer-coil-carrying member, said friction primer coil extending intothe end of the fuse-holder having the coating of friction-ignitablematerial and being of such diameter as to fractionally engage the coatedinner surface of the fuse-holder, and means by which the primer coil maybe withdrawn from the fuseholder to cause ignition of thefriction-ignitable material, after the primer-coil-carrying member hasbeen unscrewed from the support.

2. An ignition or firing mechanism comprising a support having athreaded recess therein, a fuse-holder-supporting member secured to saidsupport, a tubular fuse-holder carried by said fuse-holder-supportingmember in fixed relation the recess of the sup rt, afriction-primer-coil member carried by the primer-coil-carrying memberand having a friction primer coil extending into the end of thefuse-holder having the coating of friction-ignitable material and beingof such diameter as to frictionally engage the coated inner surface ofthe fuse holder, the friction-primer-coil member having a part thereofextending into the recess in the support, and a cord connecting saidpart of the friction-primercoil member to the primer-coil-carryingmember and normally lying within the recess.

3. An ignition or firing mechanism comprising a support having athreaded recess therein, a fuse-holder-supporting member secured to saidsupport, a tubular fuse-holder carried by said fuse-holder-supportingmember in fixed relation to said support, a delayed-action fuse securedwithin one end of said fuse-holder, the other end of the fuse-holderhaving a coating of friction-ignitable material on the inside thereof, afriction-primer-coil-carrying member screwed into the recess of thesupport, a friction-primercoil member carried by theprimer-coil-carrying member and having a friction primer coil extendinginto the end of the fuse-holder having the coating of friction-ignitablematerial and being of such diameter as to frictionally engage the coatedinner surface of the fuse-holder, the friction-primer-coii member havinga part thereof extending into the recess in the support, and a cordhaving one end connected to said part of the friction-primer-coil memberand havin its other end extending into the primer-coilcarrying memberthrough an opening therein and knotted to prevent withdrawal, toremainder of said cord normally in within the recess in the support.

4. An ignition or firing mechanism comprising a support, afuse-holder-supporting member secured to said support, a tubularfuse-holder carried by said fuse-holder-supporting member in fixedrelation to said support, a delayedaction fuse secured within one end ofsaid fuse holder, the other end of said fuse-holder having a coating offriction-ignita:ble material on the inside thereof, aprimer-coil-carrying member threaded into the support, means between theprimer-coil-carryins member and the support for making a water-tightseal between the two, a friction primer coil carried by theprimercoil-carrying member, said friction primer coil extending into theend of the fuse-holder having the coating of friction-ignitable materialand being of such diameter as to frictionally n age the coated innersurface of the fuseholder, and a pull ring secured to theprimercoil-carrying member for withdrawing the primer coil from thefuse-holder to cause ignition of the friction-ignitable material, afterthe primercoil-carrying member has been unscrewed from I the support.

5. An ignition or firing mechanism comprising a support, afuse-holder-supportlng member secured to said support, a tubularfuse-holder carried by said fuse-holder-supporting member carryingmember having a flange overlying the support, sealing means between theflange of the primer-coil-carrying member and the support for making awater-tight seal between the two, a friction primer coil carried by theprimercoil-carrying member, said friction primer coil extending into theend of the fuse holder having the coating of friction-ignitable materialand being of such diameter as to frictionally engage the coated innersurface of the fuseholder, and means by which the primer-coil may bewithdrawn from the fuse-holder to cause ignition of thefriction-ignitable material, after the primer-coil-carrying member hasbeen unscrewed from the support.

6. In a device comprising a container having therein a charge to beignited, an ignition or firing mechanism comprising a support, afuseholder-supporting member secured to said support, a tubularfuse-holder carried by said fuseholder-supporting member in fixedrelation to said support, a delayed-action fuse having one end thereofsecured within one end of the fuseholder, a quick-acting safety fusehaving one end thereof secured to the other end of the delayedactionfuse and having a part extending into contact with the charge ofignitable material, the other end of the fuse-holder having a coating offriction-ignitable material on the inside thereof, aprimer-coil-carrying member threaded into the support, saidprime-coil-carrying member having a flange overlying the support,sealing means between the flange of the primer-coil-carryins member andthe support for making a water-tight seal between the two, a frictionprimer coil carried by the primer-coil-carrying member, said frictionprimer coil extending into the end of the fuse-holder having a coatingof frictionignitable material and being of such diameter as tofrictionally engage the coated inner surface of the fuse-holder, meansby which the primercoil-carrying member may be withdrawn from thefuse-holder to cause ignition of the frictionignitable material afterthe primer-coil-carrying member has been unscrewed from the support, anda closure cap extending over the support and primer-coil-c'arryingmember and secured to the container with a water-tight connection.

7. An ignition or firing mechanism comprising a support having athreaded opening therein, a fuse-holder-supporting member secured tosaid support, a fuse holder carried by said fuse-holdersupporting memberin fixed relation to said support, a fuse secured within one end of saidfuse holder, the other end of the fuse holder having a coating offriction-ignitable material on the inside thereof, aprimer-coil-carrying member screwed into the opening of the support, afriction primer coil carried by the primer-coil-carrying member andextending into the end of the fuse holder having the coating offriction-ignitable material, said friction primer coil being of suchdiameter as to frictionally engage the coated surface of the fuseholder, and a cord connecting the friction primer coil to theprimercoil-carrying member, whereby when the primercoil-carrying memberis unscrewed from the top and pulled away therefrom the friction primercoil will move in frictional engagement with said coating offriction-ignitable material to isni the same.

JOSEPH W. VANKARNER.

